Drop bottom mine car latch



Nov. 30, 1948. R. A. SHIELDs DROP BOTTOM MINE CAR LATCH 2 Sheets-Sheetl 1 Filed Sept. 20. 1946 INVENTOR Nov; 30, 1948. R. A. sl-IIELns" 2,455,276

DROP BOTTOM MINE GAR LATCH Filed Sept. 20. 1946 2 Sheets-Sheet 2 I I I I I I I I I I I I I I I I I I I lNvl-:NToR

Patented Nov. 30, 194g 2,455,276 f DisornorroM MINE can LATCH Robert A. Shields, Bloomsburg, Pa., assignor to American Car and Foundry Company, New York, N. Y., a corporation of New Jersey Application september 2o, 194e, serial No. 698,307

1l Claims.

This invention relates to latches vin general but in Iparticular to latches intended to hold closed or release the bottom doors of mine cars.

Drop bottom mine cars are at present controlled by single part rotating hooks carried either by the car end wall or by the `car end sill. Frequently it has been impossible to apply such latch hooks to cars which were intended to voperate in low vein coal mines since the necessary unlatching motion could not be obtained with the parts located within the clearances permitted. It is an object, therefore, of the present invention to provide a latch for drop bottom mine cars which will permit the mounting of the same on cars of eX- tremely low height. I

Another object of the invention is the provision of a multi-part latch for drop bottom cars in winch the door.` engaging hook will rapidly move out or engagement with the door lug.

A still further object oi the invention is the provision of a multi-part latch for drop bottom mine cars which may be automatically retained in the released position until tripped by the closing door.

A yet further object of the invention is the provision of a latch for drop bottom mine cars with the part so arranged as to decrease the wear on the door lug and hook.

These and other objects of the invention will be apparent to persons skilled in the art from a study of the following description and accompanying drawings, in which Fig. l is a rear end View of a car with parts broken away to better disclose the latch construction;

Fig. 2 is a sectional View taken substantially on line 2 2 of Fig. 1;

Fig. 3 is an enlarged detailed view of the latch in released position, and

Fig. 4 is a sectional view taken substantially on line 4-l of Fig. 3.

Referring now to the drawings in detail, it will be seen that the latch has been applied to a mine car of more or less conventional form having wheels W supporting the car by means of axles which support the sills 2 to which are attached' the side walls fr and end walls 6. The side sills, as is customary, are-joined together by an end sill construction 8 carrying bumpers Il! and draft attachments l2.

As clearly shown the door lug is adapted to rest The space between the end sills and side sills is closed by one or more drop bottom` f much closer to the door lug on the ledge i8 of the swinging latch hook 2D. This hook is pivotally mounted as at 22 to the downturned end of an angular shaped operating handle 2li, which handle is pivoted to the car at 2G. As shown in the drawings the pivot 26 is carried by the end sheet 6 and by a bracket 28. It will be obvious, of course, that this pivot mounting for the operating handle can be carried by the end sill if it is so desired. In order to make a strong operating handle it has been built up by two angles placed with their flanges touching and welded together to give a box section handle, as

clearly shown in Fig. 2 The short anges of each angle are cut away as at 3l] in order to permit the ready mounting of pivot pin 22 and to permit the swinging of the upper end of latch hook 2t. The upper end of the latch hook is shown as located between the long flanges of the operating handle and has pivoted thereto as at 32 a strap 3,4, the opposite end of which is pivoted as at 36 to the car structure. 'Ihe torsion spring 38 has one end anchored to the car structure and the other 'end bearing on the link 34 tending to force the same in a clockwise direction as viewed in Figs. 1 and 3. In order to prevent any longitudinal shift of the hook 20 a lug 4U is formed thereon and adapted to rub on a wear plate 42 attached to the back or inner surface of the end sill structure as best shown in Fig. 2. l

Asshown in Fig. 1 the pivot pins 26 and 22 and the bearing point of door lug l 6 on hook ledge I8 are substantially in the same vertical plane when the door is latched, thus relieving the link 34 and operating handle 24 of any strain. When, howl ever, the operating handle is moved to a released position, that is, lifted from the position of Fig. 1 to the position of Fig. 3, the lower end of the operating handle will move causing the pivot 22 to swing in'a counter-clockwise direction.V Due to the anchoring of the upper end of the swinging latch hook to the car structure by link 34, the

latch will rotate also in a counter-clockwise direction relative to the car and. to the operating fhandle, but since pivot 32 is above pivot 22 the lower end of the latch hook will swing at a much greater rate than does pivot pin 22. Thus it will be seen that by properly proportioning the parts it Awill. be possible to cause the hook to swing through a distance substantially equal to the lift of the operating handle. In this way the pivotal mount 26 for the operating handle may be brought IS than has previously This will permit of the use of drop extremelyrlow vein mines. This is been possible. bottom ycars in -particularly'desirable where mechanical loading hook in the position shown in Fig. 3. When, however, the door lli is brought to closed position the lug I6 thereof will strike the projecting portion 50 of the latch hook, thereby breaking vthe toggle lock between the hook and link Sdand permitting the hook to quickly swing into engagement f-.with

the door lug. This type of. latch assembly will eliminate considerable of the wear in the hook previously caused by the scrubbingaction between the lug and the hook of the conventional 1car1when the doors are closing. Also, due to the :self-locking feature of the parts in raised posiation, thisassembly can be very readily used with automatic arm locking arrangements of the type vshown in -Patent2,376,826 granted May 22, 1945. With the type of latch assembly shown the special trackside equipment for the operating arm devscribed'in this patent can be eliminated.

vWhile the latch construction has been described more or less in detail, it will be obvious that the assembly may be readily modied and .attached to other parts oi the car than those shown and all such modications and rearrange- .ments are contemplated as will fall within the Ascope of the following claims dening my invention.

What Iis claimed is:

l. Adrop bottom mine car having a caribody and a `dumping door, a latch operator pivoted to the-car body, a latch hook rpivoted to said latch operator and swingable relative to said car body and latchoperator, means carried-by said dumpting door and engageable by saidflatch -hook to retain the 'dumping door in closed position, and

tmeans yconnected to said vlatch hook and to said-f `car to cause swinging of said rlatch hook relative tothe car body-at avrate greater than the rate of swinging of the latch operator relative to the car body.

2. Adrop bottom mine car having a car bodyA and a dumping door, alatoh operator pivoted to the-car body, a latch hook pivoted to said latch operator and swingable relative to said car body and latch'operator, means carried by-said'dump- 1`ing .do or.and engageable'by saidlatch hook to retain'the dumping "door inaclosed position, and means connected to `said latchfhook andcar body tocause swinging of the latch hook relative to the 4Vlatch operator during swinging of the latchoperator whereby said latch hook yis moved out-=of engagement with said first named means.

-3. `A-.drop bottom lmine car having ay car body `vand-adumping door, a latchoperator pivotedr-to :the car body, a latch hook pivoted to saidv latch operator and swingable relative to said-car -body and latch operator, a lug connected to said dumping door in'position to be'engaged by said latch hook to retain the dumping door inclosed posi- 'tion,and a linkr pivotallyconnected vto-said Ilatch "hookV and Ycar body, the pivotal connection beitweenjsaid link andY latch hookfbeing located `to :oneside of-theilatch hook. pivot to the'latch -operator.

' 4. rA drop `lrbottom -mine car having a carbody 1. anda dumping door, aiatch operatorf pivoted to i the car body, a latch hook pivoted to said latch operator and swingable relative to said car body and latch operator, a lug connected to said dumping door in position to be engaged by said latch hook to retain the dumping door in closed position, and a link pivotally connected to said latch hook and car body, the pivotal connection to said l latch, hook rbeing normallyV located, Tbetween 'the pivotal mountslfor said :latch operator and latch hook.

f 5. A drop bottom mine car having a car body Yand a dumping door, a latch operator pivoted to the car body, a latch hook pivoted to said latch operatonand swingable relative to said car body kand latch operator, a lug -connected to said dumpingf-doorin position. to be engaged by said latch hook to retain the dumping door in closed position, `and 'a llink pivotally connected to said latch ,hook and car body, said pivotal connections of the link and hook being so positioned as to comprisea self-locking .toggle holding the latch -hook in released position.

6. A drop bottom mine car including a car body V.anda dumping door, a latch operator, a rst pivot pin connectingan intermediate portion of said latchoperatorto the car body, a latch hook, a .second .pivot-pin connecting an intermediate portionV ofsaid latch hook to said latch operator adjacentfan end thereof, a link, a third pivot pin connecting Ione end of said link to said latch hook, a fourth pivot ypin connecting the other. end ci saidlink to said lcar body, and a lug carried by said dumping door in position Ato be engaged by said latch hookto retain the door in closed position.

'1., A dropbottcm mine car including a car body and adumping door, allatch operator, a rst pivot pin connecting an intermediate portion of said latch 'operatorto the car body, a latch hook, a ,second pivotpin connecting an intermediate por- 'Ltioncf said. latcnnook .to said laten Operator ad- .ja'centan endthereof, a link, a third pivot pin connectingone endv of said link to said latch hook, `a"fourth pivot pinconnec'ting the other end of said Ylink to s aid car body, and a ,lug carried by said dumping door in position to be engaged by said latch; hookto retain the door in closedposition, saidiirst and second pivot pins and lug being located substantially in a. common plane when said dumpingdooris being retained tin closed position.

A'drop bottom mine car including a car body anda dumping door, alatch operator, a first pivot pin connecting anintermediate portion of said 'latch Aoperator to the car body, a latch hook, a second .pivotpin connecting an intermediate .portion of said latch hook tosaid latch operator adliacentanend thereof, 4a link, .a third pivot .pin connecting one end of said link to saidlatch hook,

a founthpivot pin connecting the other end of said link to said car body, and a lug carried by said fdumpingedoor, in ,position to be engaged bysaid ...latch hook to, retain .the .door in closed. position, I, id, thirdpivonpin ybeing located slightly below aline connecting the axesof said second and foin-th pivot pinswhen the dumpingdoor is in open-.positionto thereby forni a self-locking toggle lnetainingthev latchnperator in raised position.

.",,9. A drop bottom mine car includinga car body ,anota dumping vdoor,.a latch operator, a first pivot pin ,connecting an .intermediate portion of -`said latchoperatori to the car body, `a `latch ,hook,.,a second, pivot pin connecting an .intermediate portion of said latch hook to said latch operator ,adjacent an end fthereof, a link, a third pivot pin connecting one end of said link to said latch hook, a fourth pivot pin connecting the other end of said link to said car body, and a lug carried by said dumping door in position to be engaged by said latch hook to retain the door in closed position, said third pivot pin being located slightly below a line connecting the axes of said second and fourth pivot pins when the dumping door is in open position to thereby form a self-locking toggle retaining the latch operator in raised position, and means on said latch hook engageable by said lug upon closing of the dumping door whereby said third pivot is moved above the line connecting the axes of said second and fourth pivot pins to thereby break the self-locking toggle permitting the latch hook to engage said lug.

10. A drop bottom mine car including a car body and a dumping door, a latch operator pivoted to said body, a latch hook pivoted to said latch operator and swingable relative thereto, means on said door engageable by said latch hook to retain said dumping door in closed position, and means pivotally connected to said latch hook and to said car to control the swinging movements of said latch hook.

l1. A drop bottom mine body and a dumping door, a latch operator pivoted to said body, a lug on the dumping door, a latch hook pivoted to said latch operator and swingable `into engagement with said lug to retain the dumping door in closed position, and a link connected to said latch hook and to said car body for causing a rate of swinging of said latch hook greater than car including a car that of the latch operator. 

